How do i make my mom stop?

Whenever i get on the computer my mom comes and checks every few minutes and accuses me of looking things up that im not suppose to. Mostly i watch fashion videos on youtube or play on seventeen.com. Since she tells me im wasting time i usually click out so she doesn't get upset about it and then she claims im looking up inappropriate things. Sometimes she'll make me reopen the browser and scroll through the history. She also blocks most T.V shows and movies so i can't watch them without her consent etc. etc. How can i make her stop being so protective? I haven't done anything to make her distrust me.